Mono and di lower alkoxycarbonyl substituted 10,11 - dihydro - 5,10,11-metheno - 5h - dibenzo (a,d) cycloheptenes



United States Patent Ofi ice 3,489,791 Patented Jan. 13, 1970 ABSTRACTOF THE DISCLOSURE 10,11-dihydro 5,10,11metheno-5H-dibenzo[a,d]cycloheptenes having various substituents in the5-, 12-, 5,10- or 10,12-positions are claimed. These compounds which areuseful as plasticizers for polyvinyl chloride are prepared by theultraviolet light irradiation of 9-, 11-, 9,10- or 11,12-substituted9,10 dihydro-9,10-ethenoanthracenes.

BACKGROUND OF THE INVENTION This invention relates to a substitutedpolycyclic com pounds and to the process for their preparation.

DESCRIPTION OF THE INVENTION This invention is directed to monoanddisubstituted 10,11-dihydro 5,10,11 metheno-5H-dibenzo[a,d]cycloheptenes of the formulae in sign III IV The numbering of the ringsystem 10,11-dihydro-5,10, 1l-metheno-SI-I-dibenzo[a,d]cycloheptene isThis system is also called 4b,8b,8c,8d-tetrahydrodibenzo [a,f]cyclopropa [c,d] pentalene.

The compounds of this invention are: The 5-, 10-, and 12-monosubstitutedand 5,10- and 10,12-disubstituted 10, 11 dihydro 5,10,11metheno-SH-dibenzo[a,djcycloheptenes.

The process of this invention comprises irradiating with actinicradiation, monoand disubstituted 9,10-dihydro-9,

lo-ethenoanthracenes of the formulae i I R VII VIII IX wherein R R R andR are as defined above.

Irradiation of 9,10-disubstiuted 9,10-ethenoanthracenes (VI) yields 5,10disubstituted 10,.11-dihydro-5,10,11-naetheno-SH-dibenzo[a,d1cycloheptenes (IV). Irradiation of11,12-disubstituted 9,10-ethenoanthracenes (VII) yields 10,12dihydro-5,10,11-metheno-5H-dibenzo[a,d] cycloheptenes (V).

Irradiation of the 9-1nonosubstituted 9,l0-dihydro-9,10ethenoanthracenes (VIII) yields a mixture of 5- and 10- monosubstituted10,11-dihydro-5,10,11-metheno 5H dibenzo[a,d]cycl0heptenes (I and II)whereas irradiation of ll-monosubstituted9,10-dihydro-9,10-ethenoanthracenes (IX) yields 12-monosubstituted10,11-dihydro-5,10, 1l-metheno-SH-dibenzo[a,d]cycloheptenes (III).

In the process of this invention actinie radiation such as ultravioletlight of wavelengths in the range from about 1504000 A. can be employed.Ultraviolet light having shorter wavelengths tends to promote sidereactions along with producing the compounds of the invention. The useof ultraviolet light having wavelengths above 1500 A. and particularlyin the range of 2000- 3500 A. is therefore preferred in the process ofthis invention. Irradiation is conducted at an intensity and for asufficient length of time to etfect the formation of at least some, andpreferably an economically recoverable amount of the compounds of thisinvention. Times of about 10-72 hours and longer can be used. The actualintensities and times used can be varied Widely depending on theequipment used, the wavelength of the radiation, concentration of thereactants and concentration of photosensitizer, if a photosensitizer isused.

Ultraviolet light used as the actinic radiation for the process of thisinvention emanates from commercially available ultraviolet lightsources.

The process of this invention can be carried out by irradiating thecompounds VI-IX neat, that is undiluted. The process is operable in thesolid phase. The process is also operable in liquid phase and gas phase,for example by operating at elevated temperatures or in solution.Aprotic solvents which can be used to prepare solutions include: ethers,for example diethylether, tetrahydrofuran and the like, hydrocarbonssuch as hexane, cyclohexane, benzene and the like and halogenatedhydrocarbons such as chloroform, carbon tetrachloride and the like.Protic solvents such as alcohols are op erable but aprotic solvents arepreferred.

The process of this invention is promoted by a photosensitizer, forexample acetone. The use of a photo sensitizer is accordingly preferredin the process of this invention.

Temperatures and pressures are not critical in the process of thisinvention. Room temperatures and pressures are operable, andtemperatures and pressures both above and below these can be used.Temperatures in excess of the decomposition temperature of the reactantsor products should be avoided.

The reactor for carrying out the process of this invention can beconstructed of any material which is chemically inert to the reactantsand products when the source of the actinic radiation is within thereactor. For example, glass-lined steel reactors, stainless steelreactors and the like. If an external actinic radiation source is used,the reactor must permit some reasonable transmission of the saidradiation for the ultraviolet light. When the actinic radiation isultraviolet light, quartz or Pyrex glass vessels can be used.

Isolation and separation of the products is accomplished by conventionalorganic synthetic techniques. Generally, crystallization techniques canbe used to isolate the product. Chromatographic techniques can be usedto separate the isomeric products.

Monosubstituted 9,10-dihydro-9,IO-ethenoanthracenes VIII and IX areprepared by reacting cis-l,2-dichloroethylene with 9-substitutedanthracene followed by reductive dechlorogenation using a zinc-coppercouple as described in Examples 5 and 6 and by reaction of amonosubstituted acetylene with anthracene as described in Example 4,respectively.

11,12-disubstituted 9,10 dihydro-9,10-ethenoanthracenes VI are preparedby the reaction of disubstituted acetylenes with anthracene as describedin Example 1. 9,10-disubstituted-9,10-dihydro 9,10 ethenoanthracenes VIIare prepared by the reaction of cis-l,2-dichloroethylene with9,10-disubstituted anthracenes followed by dechlorination similar to theprocess described in Examples 5 and 6.

5,10-dicyano-10,11-dihydro-5,10,1l-metheno 5H dibenzo[a,d]cyclohepteneand 5,10 dicarbomethoxy 10, 11-dihydro-5,10,11 metheno-5H-dibenzo[a,d]cycloheptene can be produced by irradiating withultraviolet light of 2000-3500 A.9,10-dicyano-9,10-dihydro-9,10-ethenoanthracene and9,10-dicarbomethoxy-9,10-dihydro-9, ethenoanthracene, respectively.

The following examples further illustrate this invention. In theexamples, parts are 'by Weight unless otherwise specified.

EXAMPLE 1 A solution of 3.082 g. of 11,12-dicyano-9,10-dihydro-9,10-ethenoanthracene in 300 ml. of benzene, contained in an internallycooled Pyrex vessel, was irradiated with ultraviolet light in aSrinivasan-Grifiin photochemical reactor (3500 A. lamps) for 64 hours.Removal of the solvent and crystallization from ethyl acetate gave 1.618

g. of 10,l2-dicyano-10,11-dihydro-5,10,1l-methano-SH-dibenzo[a,d]-cycloheptene. Removal of the solvent from the mother liquorand crystallization of the residue from ethanol-acetonitrile mixturegave an additional 834 mg. of product. Combined yield: 2.452 g. Ananalytical sample, prepared by crystallization from ethyl acetate, hadM.P. 179-180 C. N.M.R. spectrum (in perdeuterioacetone): multiplet atr2.83.3 (8H) and singlets at 74.86 (1H) and 5.44 (1H). Ultravioletspectrum:

AEQE 279 m (6 650), 271 me (e 890) and 221 my (6 28,000)

Analysis.Calcd. for C H N z C, 85.02; H, 3.96; N, 11.02. Found: C,85.37; H, 3.82; N, 10.83.

EXAMPLE 2 MeOOC cooMe A solution of 75.02 g. of9,10-dihydro-11,12-dimethoxycarbonyl-9,IO-ethenoanthracene in 750 ml. ofacetone was irradiated for 157 hours with ultraviolet light from aPhilips HPK high pressure mercury lamp. Removal of the solvent gave 76.5g. of a viscous yellow oil. It was dissolved in ml. of toluene and thecrystals were collected after standing at Dry Ice temperature for 16hours. The product weighed 43.7 g. A second crop of 25 .2 g. wasobtained by evaporating the mother liquor to dryness, dissolving theresidue in 50 m1. of methanol and collecting the crystals formed afterstanding at room temperature for 16 hours. Combined yield of10,11-dihydro- 10,l2-dimethoxycarbonyl-5,10,1l-methano 5H dibenzo[a,d]cycloheptene: 71.9 g. (96%). An analytical sample, prepared bycrystallization from methanol, had M.P. 9899 C. N.M.R. spectrum (in CDClmultiplet at 72.6 to 3.1 (8H) and singlets at 14.97 (1H), 5.51 (1H),6.17 (3H) and 6.32 (3H). Ultraviolet spectrum: m5 279 my (6 1200), 271111;: (e 1500), 265 m (e 1400) and 217 m (shoulder, 6 25,000)

Analysis.Calcd. for C H O C, 74.99; H, 5.03. Found: C, 74.98; H, 5.32.

The same product was obtained using either cyclohexane or benzene as thesolvent and two Westinghouse RS sunlamps as light sources.

EXAMPLE 3 A solution of 4.68 g. of 1l,12-bis(trifluoromethyl)-9,10-dil1ydro 9,IO-ethenoanthracene in a mixture of 300 m1. of benzeneand 5 m1. of acetone was irradiated with ultraviolet light from aPhilips HPK 125 high pressure mercury lamp for 21 hours. Removal of thesolvent and crystallization of the residue from 10 ml. of 70% aqueousethanol gave 3.45 g. (74% yield) of10,12-bis(trifiuoromethyl)-10,11-dihydro-5,10,11-methano 5H dibenzo-[a,d] cycloheptene. An analytical sample (ethanol) had M.P. 81.5-82.5 C.Proton N.M.R. spectrum (in CdCl multiplet at 72.5 to 3.2 (8H) andsinglets at 15.10 (1H), and 5.86 (1H). Ultraviolet spectrum:

A53? 278 n1;1(e 800), 270 m (6 960), 264 ma (6 780) and 215 m (6 28,000)

Analysis.Calcd. for C H F C, 63.53; H, 2.96; F, 33.50. Found: C, 63.52;H, 3.10; F, 33.47.

EXAMPLE 4 Part A A deoxygenated mixture of 10 g. of anthracene and 25 g.of methyl propiolate, contained in a Carius tube, was heated to 200 C.for 12 hours. The tube was rinsed out with methylene chloride, thesolvent was removed, and the residue was crystallized from 50 ml. oftoluene giving 6.81 g. of 9,10-dihydro-11-methoxycarbonyl-9,10-ethenoanthracene. A further 1.79 g. of product was obtained byconcentrating the mother liquor to dryness and crystallizing the residuefrom 30* ml. of acetonitrile. Combined yield: 58%. An analytical sample,M.P. 179.5- 180.5 C., was prepared by crystallization from acetonitrile.N.M.R. spectrum (in CD01 doublet (J=6.1 cps.) split into doublets (1:1.9c.p.s.), centered at 12.13 (1H), rnultiplet at 12.5 to 3.2 (8H): doublet(1:1.9 c.p.s.) at 14.33 (1H), doublet (1:6.1 c.p.s.) at 14.80 (1H) andsinglet at 16.30 (3H). Ultraviolet spectrum:

AfiE 278 mp. (e 3100), 272 Ill/L (e 2600) and 214 my (6 12,000)

A.nalysis.Calcd. for C H O C, 82.42; H, 5.38. Found: C, 82.58; H, 5.43.

Part B A deoxygenated solution of 6.03 g. of 9,10-dihydro-11-methoxycarbonyl-9,10-ethenoanthracene in 400 ml. of acetone, containedin an internally cooled Pyrex vessel, was irradiated with ultravioletlight from a Philips HPK 125 high pressure mercury lamp for 14 hours.Removal of the solvent gave 6.037 g. of a pale yellow solid, the N.M.R.spectrum of which showed the presence of more than 95% of the12-methoxycarbonyl isomer (see below). A small amount of the 10-isomermay have been present. Crystallization of 4.99 g. of the product from amixture of 25 ml. of ethanol and 15 ml. of ethyl acetate gave 3.74 g.(75% yield) of 10,1l-dihydro-l2-methoxycarbonyl-5,-10,1l-metheno-SH-dibenzo-[a,d]cycloheptene, M.P. 169.- 170.5 C. N.M.R.spectrum (in CDCl;,): multiplet at 12.6 to 3.1 (8H) and singlets at15.03 (1H), 6.23 (2H) and 6.32 3H). Ultraviolet spectrum:

Axis 280 my (6 1600); 272 m (6 1900); 266 111;; (e 1500); and 220 m (627,000)

Analysis.-Calcd. for C H O C, 82.42; H, 5.38. Found: C, 82.20; H, 5.42.

EXAMPLE 5 Part A A mixture of 9.62 g. of 9-nitroanthracene and 35 ml. ofcis-l,Z-dichloroethylene, contained in a sealed Carius tube, was heatedto 200 C. for 24 hours and then to 230 C. for 48 hours. The product waspassed through g. of magnesium fluorosilicate and eluted with 600 ml. ofmethylene chloride. Further purification by crystallization from toluenegave 8.08 g. of 11,12-dichloro-9,l0-dihydro-9-nitro-9,lO-ethanoanthracene, M.P. l 86188 C.

Part B A zinc-copper couple was prepared by treating 15 g. of zinc dustwith 400 ml. of a 2% aqueous solution of copper sulfate. It was washedwith ethanol and added to a suspension of 6.188 g. of11,l2-dichloro-9,10-dihydro-9-nitro- 9,10-ethanoanthracene in 200 ml. ofethanol. After heating under reflux for six hours, the mixture wasfiltered while hot, and the solids were washed with boiling ethanol. Thecombined filtrates were evaporated to dryness and the precipitate wastreated with 10% aqueous hydrochloric acid. The residue was collected byfiltration, washed with methylene chloride and water, and dried. Thehydrochloride so obtained was suspended in water and treated withpotassium hydroxide pellets. The mixture was extracted with ether, andthe ether extracts were dried over potassium hydroxide. The removal ofthe solvent gave 3.027 g. of 9-amino-9,l0-dihydro-9,10-ethenoanthracene,M.P. 146-149 C. after crystallization from ethanol. The N.M.R. spectrumshowed a multiplet at -3.5 (8H), a doublet of doublets at 15.0 (1H) anda broad singlet at 17.8 (2H).

Part C A deoxygenated solution of 716 mg. of 9-amino-9,10- dihydro9,10-ethenoanthracene in 125 ml. of acetone in an internally cooledPyrex vessel was irradiated for 15 hours with ultraviolet light from aPhilips HPK 125 high pressure mercury lamp. Removal of the solvent gavea mixture of the 5- and 10-amino-10,l1-dihydro-5,10,11-metheno-SH-dibenzo[a,d]cycloheptenes having the following N.M.R.spectrum: multiplets at 12.33.3 (8H) and 15.87.1 (3H) and broad singletat 15.5 (21-1).

7 EXAMPLE 6 coo COOMQ COOMe OOMe COOMe Part A A mixture of 10.00 g. of9-me-thoxycarbonylanthracene and 35 g. of cis-1,2-dichloroethylene,contained in a sealed Carious tube, was heated to 240 C. for 48 hours.Removal of the solvent and chromatography of the residue over 80 g. ofmagnesium fluorosiilcate gave 14.74 g. of a brown oil, eluted with 1000ml. of methylene chloride. The product was dissolved in 80 ml. ofboiling methanol. On cooling, 8.27 g. (59% yield) ofcis-11,12-dichloro-9,10- dihydro-9-methoxycarbonyl-9,10 ethanoanthracenewas obtained. An analytical sample, prepared by crystallization fromisopropyl alcohol, had a melting point of 161.5- 162.5 C.

Analysis.Calcd. for C H CI O C, 64.88; H, 4.24. Found: C, 63.26; H,4.39.

Part B A zinc-copper couple was prepared by treating 3.8 g. of zinc dustwith three -ml. portions of 2% aqueous copper sulfate solution followedby washing with 50 m1. of ethanol. It was then added to a solution of1.895 g. of cis- 11,12-dich1oro=9,10-dihydro-9 methoxycarbonyl 9,10-ethanoanthracene in ml. of ethanol. After heating under reflux for sixhours, the mixture was filtered while hot, and the solids were washedrepeatedly with hot ethanol. The combined filtrates were evaporated todryness. The residue obtained was dissolved in methylene chloride andwashed with 3% aqueous hydrochloric acid, 5% aqueous sodium bicarbonatesolution, and concentrated sodium chloride solution, and dried. Removalof the solvent and crystallization of the residue from isopropyl alcoholgave 1.238 g. (83%) of 9,10-dihydro-9-methoxycarbonyl-9,10-ethenoanthracene. An analytical sample, prepared by recrystallizationfrom isopropyl alcohol had a melting point of 139-140 C. N.M.R. spectrum(in CD01 multiplet at72.5-3.1 (10H); doublet (J :6 c.p.s.) split intodoublets (J=1.5 c.p.s.), centered at 74.91 (1H) and singlet at 75.94(3H). Ultraviolet spectrum:

12, 52 278 mp.(6 2500), 271 mll,( 1500), 263 my (6 800), and 215 m,u(e38,000).

Anaylsis.Calcd. for C H O C, 82.42; H, 5.38.' Found: C, 82.12; H, 5.62.

Part C A deoxygenated solution of 1.047 g. of 9,10-dihydro-9-meth0xycarbonyl-9,IO-ethenoan-thracene in 200 ml. of acetone,contained in an internally water-cooled Pyrex vessel, was irradiatedwith ultraviolet light from a Philips HPK high pressure mercury lamp for16 hours. Removal of the solvent and chromatographic separation of theresidue on a magnesium fluorosilicate column gave 955 mg. (91% yield) ofa mixture of the 5- and 10-isomers ofmethoxycarbonyl-10,11-dihydro-5,10,11-metheno-5Hdihydro-5,10,11-metheno-5H dibenzo[a,d]cycloheptene in the ratio of67:33. The earlier fractions (benzene-n-hexane 7:3) contained the5-isomer; the 10-isomer was eluted completely only with CH cl-tetrahydrofuran 9:1.

The 5-isomer, after two crystallizations from methanol, had a meltingpoint of 101-102 C. N.M.R. spectrum (in CDCl;.;): multiplet at 72.4 to4.1 (8H); triplet (1:6.5 c.p.s.) centered at 75.96 (1H); singlet at76.20 (3H) and doublet (J :65 c.p.s.) centered at 76.92 (2H).Ultraviolet spectrum:

Ax??? 281 m (shoulder, e 1400), 273 m,u(e 1900), and 215 m,u(38,000).

Analysis.Calcd. for C H O C, 82.42; H, 5.38. Found: C, 82.02; H, 5.41.

The 10-isomer, after two crystallizations from isopropyl alcohol, had amelting point of 129-130 C. N.M.R. spectrum (in CDCl;,): multiplets at72.1 to 2.3 (1H) and 2.6 to 3.2 (7H); doublet (J=5 c.p.s.) centered at75.50 (1H); multiplet at 75.9 to 6.1 (2H) and singlet at 76.23 (3H).Ultraviolet spectrum:

AMeCN 280 m,u(e 1400) 272 m e 2100 and 223 e 27 000). M

EXAMPLE 7 A solution of 2.067 g. of polyvinyl chloride (Geon 103 EP) in20 ml. of tetrahydrofuran was divided into two equal parts, A and B. ToA was added 0.5 g. of 10,11-dihydro-IO,12-dimethoxycarbonyl-5,10,1l-metheno 5H- dibenio[a,d]cycloheptene. Films were cast from the two solutions. The film fromA was plasticized and was flexible and tough. The film from B was stiffand brittle.

and

wherein R R and R are lower alkoxycarbonyl.

2. The compound of claim 1 wherein R and R are methoxycarbonyl; saidcompound being 10,12-dimethoxy- 10 carbonyl- 10,1 1-dihydro-5,10,1l-metheno-SH-dibenzo a,d] cycloheptene.

3. The compound of claim 1 wherein R is methoxycarbonyl; said compoundbeing 12-methoxycarbonyl-10, ll-dihydro 5,10,11 metheno-5H-dib cnzo[a,d]cycloheptene.

4. The compound of claim 1 wherein R} is methoxycarbonyl; said compoundbeing 5-methoxycarbonyl-10,l1- dihydro5,l0,1l-metheno-SH-dibenzo[a,d]cycloheptene.

References Cited UNITED STATES PATENTS 3/1961 Krespan et al.

OTHER REFERENCES Emerson et al.: J. Am. Chem. Soc., vol. 87, pp. 131-133 (1965).

Zimmerman et al.: I. Am. Chem. Soc., vol. 88, pp. 183-184 (1966).

CHARLES B. PARKER, Primary Examiner S. T. LAWRENCE III, AssistantExaminer US. Cl. X.R.

"H050 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. l89,79l Dated Januarv D, 1970 Inventm-(s) Engelbert Ciganek It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

[- Column 1, line 26, delete the word "a";

Column 2, formula IX, "-R should be -R Column lines 1, 36 and 66,correct the spelling of metheno each occurrence;

Column 7, line 55, correct the spelling of Carius Column 8, line 52,delete the following: "hydro- 5,lO,ll-metheno-5H-di"; line 38, "to hl"should be to 3.1 line &3, "215 mp. should be 219 mu. line 44,

C H O should be C H O line 58, "-dicarboxyl-" sh d ld b -dicarboxy 2SIGNED AND SEALED AUG4.1970

(SEAL) Atteat:

Edward M- F m I wmnu I. suaumm. .m.

testing Officer Comiulonn of Patents

